Athletes who have had rules changed or made based on them...

Hey all,
Working on an enterprise piece about athletes who have "changed the game." Basically, I'm trying to come up with as many athletes as possible who have had a move or done something so unstoppable or tremendous that their respective sport's governing bodies have made changes to slow or stop them.

For instance, the head slap was outlawed essentially because Deacon Jones had mastered it and nobody could block him. Eventually everyone else started mimicking it and they banned it. Or MLB lowering the mound soon after Bob Gibson posted the 1.12.